Mining-machine.



C. H. BOARDMAN.

MINING MACHINE.

APPLICATION mm fzs. 5. 1915.-

N 1,199,757. Patented oct. 3,1916.

CHARLES H. BOADMAN, 0F VIVIAN, WEST VIRGINIA, ASSIGNOR T0 YSUNDRIES, MANUFACTURING COMPANY, 0F PORTLAND, MAINE, A CORPQRATION 0F MAINE.

MINING-MACHINE.

To all whom t may concern:

Be it known that I, CHARLES H. BOARD- MAN, a citizen of the United States, residing at Vivian, in the county of McDowell and State of West Virginia, have invented certain new and useful Improvements in Mining-Machines, of which the following is a specification.

This invention is a machine of the type which` acts to undercut the mineral at the end of a heading, or -any other wall of a passage or chamber in a mine, being particularly designed for coal mining, although not limited in this respect.

Attempts have heretofore been made to utilize machines which have only a single cutting mechanism, so located with respect to the frame of the Amachinelthat when the latter is placed on the ioor of a mine, and brought up tol the'wall from which the mineral is to be cut, a narrow slit extending horizontally into the wall nearthe floor will be made. Such machines are unsatisfactory in their operation, because the slits produced are usually so shallow E` that when the superposed mineral is broken down by wedging or blasting, the mineral is not broken into suiiciently small lumps-for convenient and practical loading and handling, exceptI by employment of an excessively large charge of explosive, but is loosened as a large mass of, perhaps, several tons in weight, which must be subsequently shot or picked to pieces. Another method of obtaining pieces of convenient size by employing a shallow undercut, is by making a heavy blast and breaking the mass of coal by the force of the blast. This, however, is wasteful of explosive, and has the additional disadvantage of shattering the coal too much, with production of too large a proportion of dust.

My invention aims to overcome the.objec tions above indicated, by providing a simply constructed and easily operated machine for making a deep undercut, by means of spaced apart cutting mechanisms located one above the other, with a clear space between them, to the end thatthe machine may make two separated cuts simultaneously, and at the same time remove the mineral between the cuts. The upper cutting mechanism is arranged to cut into the mineral wall to a greater depth than the lower cutting mechanism, whereby, when the cutting actlon has Specification of Letters Patent.

been completed, a deep undercut is produced- 'ported at the back and .unsupported at the front, and when said mineral is brought Patented @ct-3, 11916.v Application area February 5, 1915. serial No. 6,326. l

down by any of the commonly practised methods, this motion causes it to break into sufficiently small lumps,` and out into the room, so that it may be conveniently handled.

A further object is to provide means for weakening the strata of the-coal being operated upon by the cutting mechanisms, whereby the mass is caused to drop and be conveniently removed by the cutting mechanisms in-their operation.

The invention will be hereinafter fully set forth and the claims.

In the accompanying drawings :-Figure 1 is a side elevation illustrating my invention, the mineral wall being shown in section, the frame of the machine -and the power mechanism being conventionally shown. Fig. 2 is a plan view. Fig. 3 repparticularly pointed out in resents a section of the mine wall, illustrating the character of the work performedby the machine. Figs. 4 and 5 are detail views illustrating the supplemental cutter located between the cutting mechanisms.

Referring to the drawings, 10 designates the (frame of the machine, of any suitable or preferred construction, which contains in .its interior the power mechanism and connections for operating the parts, and from which extend two arms 11, 12, one directly above the'other.V The arm 11 is longer than the arm 12, the arrangement being such that the forward end of the upper arm extends beyond the-forward end of the lower. arm. Both arms are Yconstructed with guide-ways at their edges, and guide wheels or pulleys, through and about which pass endless chains 14E,v 15, respectively, carrying cutters or bits 16. Where the chains pass into the frame or casing 10, they are 'supported and driven by suitable drive wheels or sprockets (not shown). By the foregoing arrangement the working extremity of the upper chain extends beyond lthe working extremity of the lower chain.- As appears from the side view (Fig. 1), certain of the' cutters are odset respectively upwardly and downwardly from the carrying chain to a distance somewhat above and below the supporting arm, while other cutters extend straight out from the chain. This arrangementy is for the purpose of enabling the slot-cut, to be somewhat wider than the arm, and to aord sufficient clearance for the same.

Interposed between thev arms 11 and' 12,

and mounted upon a horizontal axis is a` star-shaped cutter 17, the shaft of which is mounted in bearings carried by a rotatable ring 18. 'lhe cutter 17 is supported by the upper arm 11 at a point directly abovethe cutting extremity of the lower chain. C

At the rear ofthe machine are lugs 20, 21,

betweenwhich are guide pulleys 22 and op- The internal construction of the machine,A

and the driving' motor inclosed in the frame or casing 10, have not been illustrated, for

the reason that such construction and motor form no part of my present invention, and it is suiiclent for the purposes of the invention, that the cutter carrying chains are driven by any suitable form of motor and transmission mechanism.

In operation, the machine is brought up to the wall to be attacked, at one end or side of the passage or room 26, and is fed forward into the wall as fast as the cutters re move the mineral. As the cutters advance, the points' of the cutter 17 project inthe direction of travel, said cutter being so lo- '45. cated that it will be engaged in the solid coal between the .upper and lower cutters, and not touch the upper side of the kerf, thus compelling it to dig or gouge chunks out of the solid intervening block. This necessarily weakens the strata of coal, and

vthe bits in the chains, working so close to it, will compel the whole mass to drop and be taken out by the action of the chains. As the cutters advance, the mineral between the arms 11 and 12 falls by its own weight and disintegrates, breaking up into pieces'A small enough to be removed by the chains. When the cutter carrying arms have been advanced` the machine as a whole as far as practicable,

lthe wall, as far as is moved sidewise acroSS desired, whereby a slot parallel with thel floor, having the desired extent, is produced. This. slot or kerf is shown in cross section, both in Figs. 1 and 3. The mineral between the cutter being thin, ornarrow, and weakened by the cutter 17, sags down and is broken and dragged out in piecesv of sizes known as egg and lump sizes or grades,

the removal of the broken pieces being effected by the upper and lower cutters and chains, which travel in the same direction. Thus all the mineral between the uppermost and lowermost cutters is removed, whereupon a single,`wide undercut is left, provided with the overhang 26a. The material in the wall above this wide undercut may then be broken down by any of the commonly used methods, and in a way such as to produce the desired size, the height of the undercut being such that the overhanging mass, in falling to the bottom of the cut, fulcrums on the overhanging portion and strikes the bottom with suiicient force to be broken into lumps not too large to be conveniently loaded by the miners into mine cars, without requiring a blast heavy enough to crush the coal by the force of the blast alone, and without causing the vcoal to be so much crushed as to be pulverized to any `great extent. No power is applied to the cutter, other than the motion of the machine as it moves, the path lfollowed by the cutter 17 being indicated in Fig. 6. In operation, the points of the cutter 127 that extend above the axle of the cutter, do not touch any coal, but the points below the axle engage the broken down coal between the chain cutters. When the machine is propelled inany one direction, the depending points of the cutter being in contact with the top of the broken down coal, the cutter is caused to revolve,

and as it comes 1n contact with the top of the coal it necessarily digs itself down into the same. When the machine is made to cut in a direct right angle to the direction of travel at any one time, the fact that but two of the cutting points of the cutter 17 can be engaged in cutting coal at one time, causes one o the points to be deeper irito the coal than the other, and consequently, when themachine is turned, thepo'int of the cutter that is deeper in the coal than the other one, will not be moved as quickly as the one that is not so firmly embedded, and therefore the line in which the axle of the cutter 17 revolves, must turn so as to push the star in position to run in the same direction as the machine will then be going. In other words, the .instant that the point of the star cutter ives in the least, the whole horizontal bearing ring 18 will immediately turn so as to allow the cutter 17 to work in the direction required. As the machine penetrates the wall of coal the cutter 17 follows the path indicated at- 26 until the machine has en` tered tothe desireddepth. When the machinestarts its lateral movement, the ring 18 is causeduto make a quarter turn, where.- upon the cutter 17 follows the path indi-l cated at 27. When the lateral cut is completed, andthe machine is to be withdrawn,

the bearing ring l18 is again turned a quarter turn, causing the cutter 17 to follow the path indicated at-QS.

The above described machine is specially adapted for us'e in mining soft coal', .although it is not lilnited to this particular kind of coal. Its particular advantage lies in the fac't that the kerf or slot formed by it is very similar in form and style to that made by the lniner when using hand tools. It thus has all of the advantages of hand min-` ing, in that the coal instead of coming straight down, is caused to come down with a rolling or forward motion, because of the fulcrum formed at the back of the kerf, is removed in moderately large lumps, with the production of a minimum proportion of dust or finely granulated coal. It also possesses the additional advantage that the coal may be rapidly and economically mined.

Having thus explained the nature of lmy invention and described an operative manner of constructing and using the same, although without attempting to set forth all of the forms in which 1t may be made, or all of the forms of its use, what I claim is 1. A mining machine of the character described comprising a frame, spaced apart endless chains carried by said frame and arranged one vabovethe other, the forward working extremity of the upper chain extending beyond the forward working eX- tremity of the other chain, and cutters carried by said chains for cutting the material and removing the severed material as the" cutting progresses.

2. mining machine of the character described comprising a frame, spaced apart endless chains carried by said frame and arranged one above the other, cutters carried by said chains for cutting the material and removing the severed material as the cutting progresses, and a cutting wheel mounted bethe Working extremity of the shorter chain. y

l. A mining machine of the character described comprising a frame, spaced apart endless chains carried by said frame and arranged one above the other, cutters carried by said chains for cutting the material and removing the severed material as the cutting progresses, a cutting wheel mounted between the chains and rotatable on a horizontal axis, and a support for said cutter rotatable upon a vertical axis. t

In testimony whereof I have aliixed my signature, in presence of two witnesses.

CHARLES H. BOARDMAN.

Witnesses:

' M.` C. TROVINGER, 1 J. M. HUDDLEsToN. 

